System and method of use for conducting a neutral corrosion surv

Details System and method of use for conducting a neutral corrosion surv System and method of use for conducting a neutral corrosion surv

1995-12-12

1997-08-05

Wieder, Kenneth A.

Electricity: measuring and testing

Fault detecting in electric circuits and of electric components

Of individual circuit component or element

324523, 324713, 324718, 324 67, G01R 3102

Patent

active

056546424

ABSTRACT:
A system and method for testing underground electric cables, while in service, for active corrosion and degree of neutral loss. The method is conducted by applying a non-harmonic selected frequency signal to the neutral(s) of the underground cable connecting a pair of structures, e.g., power transformers, from a variable frequency generator of the system. The test is conducted by a surveyor wearing foot electrodes which contact the earth as the surveyor walks along the earth over the cable in close interval steps. At each step, direct current (DC) potentials are monitored by a voltmeter between a copper-copper sulfate electrode carried by the surveyor and brought into contact with the ground at each step and the transformer ground. The potential of the gradients between the foot electrodes at the selective frequency and at the native alternating current (AC) is also measured by the voltmeter. These measurements are recorded at a stationary location on a digital data logger and/or computer. At all points of direct current or selective frequency potential abnormalities, a waveform is recorded of both potentials, as well as peak-to-peak potential measurements, maximum potential, minimum potential, mean potential, frequency, rms voltage, and soil resistivity to generate a continuous corrosion and condition profile of the entire length of cable including permanent land features.

REFERENCES:
patent: 3289076 (1966-11-01), Edis et al.
patent: 3792350 (1974-02-01), Bossler et al.
patent: 3991363 (1976-11-01), Lathrop
patent: 4151458 (1979-04-01), Seager
patent: 4835478 (1989-05-01), Haddon et al.
patent: 4839598 (1989-06-01), Calvert et al.
patent: 4929901 (1990-05-01), Kimball et al.
patent: 4947469 (1990-08-01), Vokey et al.
patent: 5101161 (1992-03-01), Walsh et al.
patent: 5126654 (1992-06-01), Murphy et al.
patent: 5210498 (1993-05-01), Paananen
patent: 5347212 (1994-09-01), Bass et al.
patent: 5451862 (1995-09-01), Bass et al.
Maloney, "Locating Cable Faults", Jul./Aug./1973, pp. 380-394.
Baver, "Overground Method Pinpoints Concentric-Neutral Corrosion", Jul. 1989, pp. 49-53.
Zastrow, "Underground Corrosion Control and Direct Buried Cables: Cost-Effective Steps for a Complete Program", (no date available), pp. 63-72.
Woodsmall et al., "Cathodic Protection of Existing URD Systems", (no date available), pp. 77-87.
Wagner et al., "Concentric Neutral Corrosion And Its Control", (no date available), pp. 121-126.
Silver, "Underground Distribution Cable Designs Resistant to Concentric Neutral Corrosion", (no date available), pp. 127-138.
Waits, "Concentric Neutral Corrosion--Field Tests and Data Evaluation", Apr. 1981, pp. 143/1-143/12.
Haynes et al., "Evaluation of Steel Clad Copper Concentric Neutral Wires in Service", Apr. 1981, Paper 144, pp. 144/1-144/17.
Compton, "The Underground Corrosion of Copper and the Effects of a.c. on Concentric Neutrals of URD Cable", Apr. 1981, Paper 145, pp. 145/1-145/15.
Kroon, "URD Corrosion Experience" Apr. 1981, Paper 146, pp. 146/1-146/15.
Mitchell, "Concentric Neutral Corrosion Effects on Electrical System Operation", Mar. 1980, Paper No. 1, pp. 1/1-1/5.
Compton, "Mechanisms in the Underground Corrosion of the Concentric Neutrals of URD Cable", Mar. 1980, Paper No. 271, pp. 271/1-271/8.
Haynes et al., "Update on the Corrosion of Steel Clad Copper Concentric Neutral Wire", Apr. 1984, Paper No. 278, pp. 278/1-278/9.
Compton, "The Effect of Variations in the Sulfate and/or Chloride Ion Concentration of the Underground Corrosion of Copper", Apr. 1984, Paper No. 279, pp. 279/1-279/17.
Woodsmall et al., "Cathodic Protection of URD Cable Concentric Neutral Wires", Apr. 1984, Paper No. 280, pp. 280/1-280/20.
Zastrow, "Defining Corrosion Control Requirements from As Found Measurements Along Underground Cables", Apr. 1984, Paper No. 281, pp. 281/1-281/17.
Giesler, "Cathodic Protection of Copper Concentric Neutral Cables on The PP&L System", Apr. 1984, Paper No. 282, pp. 282/1-282/12.
Zastrow, "Guide for Underground Corrosion Control on Rural Electric Systems," (no date available), pp. 1-75.

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